Ice crusher



March 1965 R. s. KNAPP ETAL 3,171,505

ICE CRUSHER Filed Aug. 27, 1962 2 Sheets-Sheet 1 FIG. 2

Inventors. Robert S. Knapp Alfred J. Huck B M March 1965 R. s. KNAPP ETAL 3,171,605

ICE CRUSHER Filed Aug. 27, 1962 2 Sheets-Sheet 2 inventors. Robert S. Knapp Alfred J. Huck 3,171,605 Patented Mar. 2, 1955 ice 3,171,605 ICE CRUSHER Robert S. Knapp and Alfred J. Huck, St. Louis, Mo., assignors to Knapp-Monarch Company, St. Louis, M0,, a corporation of Delaware Filed Aug. 27, 1962, Ser. No. 219,454 1 Claim. (Cl. 241-257) This invention relates to an ice crusher and more particularly to an ice crusher having rotatable ice-crushing means therein adapted to be driven by an improved and simplified construction.

Ice comminuters or crushers, of the type which receive ice in block, or cube, form and grind it up with rotatable means and then utilize the centrifugal force of the rotating means to discharge the ground up ice laterally of the motor drive for the ice crusher, have been employed in the home to provide ice for drinks and the like or for iced confection, as for example snow cones. Such ice crushers have utilized comparatively expensive, powerful, high speed motors of the A.C.-D.C. universal type which develop speeds on the order of 10,000 to 18,000 revolutions per minute. In view of the high cost of such motors, manufacturing practices suggest utilization of lowcost motors to drive the ice crusher. However, various low-cost motors have been tried, but such attempts have been unsuccessful. Some low-cost motors have adequately high speed but do not have sufiicient power to effectively crush the ice cubes. Other low-cost motors of the shaded-pole induction type, for example, rotated more slowly but as soon as an ice block is dropped into the hopper of the ice crusher, the rotating crusher mechanism will stall.

Thus, one object of the present invention is to provide an improved ice crusher construction wherein the disadvantages and deficiencies of prior constructions are obviated.

Another object of this invention is to provide an improved ice crusher utilizing a relatively inexpensive shaded-pole induction motor for driving the rotating crusher mechanism within the ice crusher.

Another object of the present invention is to provide an improved ice crusher utilizing a small, inexpensive, limited-torque motor for driving the ice crushing means and having energy storage means connected to the motor for maintaining rotation of the motor during the ice crushing operation.

A still further object of the present invention is to provide an ice crusher having rotary ice-crushing means therein driven by a relatively small shaded-pole induction motor having an output in the range of only 4 to 16 watts and/ or only 3 to inch-ounces of torque, and utilizing flywheel means for the motor so that the weight of the flywheel combined with the weight of the ice-crushing means and rotating elements of the motor being in the range of 12 to 50 ounces, thereby producing a device which maintains rotation of the motor during ice-crushing operation.

Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

A preferred embodiment of the invention is shown in the accompanying drawings, in which:

FIG. 1 is a perspective view showing the ice crusher construction of the present invention;

FIG. 2 is an enlarged vertical cross-sectional view of an ice crusher construction, as illustrated in FIG. 1;

FIG. 3 is a cross sectional view taken substantially on the line 33 of FIG. 2 and shows the interior of the ice crusher looking downwardly on the ice comminuting and centrifugal discharging means; and

FIG. 4 is a plan view of the flywheel construction of the present invention.

Referring now to the drawings, there is shown in FIG. 1 an ice crusher, indicated generally at 10, mounted atop a base, indicated generally at 12, within which is positioned a drive motor for driving ice crushing elements within the ice crusher 10. a The base 12 is of the type which may be used for food comminuting or drink blending machines, and includes a casing 14 from which extends an on-off control switch 16 for controlling the drive motor positioned within the base. Electric power may be supplied to the drive motor via the electric cord 18. The details of the base 12 need not be disclosed herein, but the construction may, for example, be similar to that disclosed in United States Patent No. 2,585,255.

The ice-crushing mechanism is housed within a molded plastic casing 20. A cover 22 is pivoted upon the casing 20 about the hinge means 24 to permit selective-entry of individual ice cubes into the casing 20. Crushed ice is to be discharged through the discharge means 26, formed integrally with the casing 20, into a suitable container (not shown).

Referring now to FIG. 2, there is illustrated a cross sectional view of the ice crusher construction of the present invention. As seen in FIG. 2, the hinge means 24 is formed integrally with cover 22 and includes stud means 25, such as a pair of fingers, adapted to extend through openings 23 in the upright wall of easing member 20. Inasmuch as the cover and hinge means are preferably formed from plastic, it is relatively simple to heat-upset the ends of the studs 25, thereby providing fastening means for securing the hinge means to the casing member 20. It will be understood that by virtue of the inherent resiliency in the hings means 24, the cover 22 will normally be self-closing. The casing which is generally referred to at 10 hereinabove, includes both a mounting plate 28 and a molded casing member 20 formed of plastic and secured to the mounting plate by means of a plurality of screws 30 (FIG. 3). The hollow casing member 20 partially defines and surrounds an ice-crushing chamber, generally noted at 32, within which the icecrushing or comminuting takes place. The casing member 20 also defines an upright, first elongated passageway 34 through which ice in the form of blocks, or chunks, may be introduced or advanced downwardly toward and into the ice-crushing chamber 32. There is also defined in the discharge means of casing 20 a second laterally extending elongated passageway 36, which extends generally transversely of the first passageway 34, and which communicates with the ice-crushing chamber 32 and through which comminuted, or crushed, ice is delivered laterally from the ice-crushing chamber 32.

More specifically, the second passageway 36 is defined by an upper side 38 of the discharge means 26, which is part of the casing member 20, and by a lower side, which is part of the mounting plate 28, and spaced upright sides, one of which is part of the exterior wall of discharge means 26 of the casing member 20 and the other being an interior wall 88 which is molded integral with the easing member 20. The longitudinal axis of the second passageway 36 is laterally offset and transverse to the longitudinal axis of the first passageway 34 and the longitudinal axis of the second passageway 36 is also laterally oflset from the axis of rotation of the ice-crushing means 40, so that passageway 36 is, preferably, tangential of said means 40.

The ice-crushing-and-discharging means 40 are essentially the same as that described in the co-pending application Serial No. 5,054 filed by Alfred J. Huck on January 3 27, 1960, now Patent No. 3,051,401. The ice-crushingand-discharging means comprise a disc member 40 which is of generally frusto-conical in shape with a central dished portion 44 wherein is located aclamping nut 46 for fastening the disc member. 40'to a rotatable shaft: 56. The

greate pprtionof the disc member 40-is a frusto-conical" locates the upper edgesofjthe cuttersSO and 52 close to, the: lower terminus of the first passageway 34, so that blockice enteringthe cutting chamber 341s immediately engaged by the rapidly rotating cutters t) and 52, and is ground up. They longitudinal axis of passageway 34 is located rearwardly of the axis of disc 40', as best seen in FIG. 2, so that there is little tendency-of large pieces,

of, ice being'forced' out of the device through passageway 36, Theice-cr-ushing means 40 also cooperates with the sidesjofj the first passageway which seek to restrain the block of ice that is being fed into the ice-crushing. chamber 32, so that the rotary action of, the disc, 40

It will be understood that these cooperatiing surfaces defined by liousing'are plastic, and the relatively low heatconductivity of the plastic prevents ice accumulations on; the surfaces of the housing20. The feature of having a housing 20' formed of plastic has been found to provide an adyantage in that. the-shaved.ice does,not adhere to it and cons quently there is no build-up of ice on the walls. thereof'which. might interfere with proper operation of the device.

The particular disposition of, the, cutting disc 40." thatishere utilized is also desirable with regard to the using of centrifugal force to discharge the ground-up ice,from the device Theground ice ejector 54proyides the nec essary tangential impetus, and the centrifugal force operates,to throw the comminuted' ice particles laterally through the passageway, 36'from whence the particles are directed downwardly through discharge opening by means of; the downwardly curved wall 38a which is an extension of the top wall38 and which is spaced, from theterminal end of the mounting plate 28 as best seen irrFLG; 2'.

The ice:crushing anddischarging means 40. are driven by an improved drive mechanism housed within the casing lt. Connected to and supporting the disc gis a shaft. 56, which is driven by a shadedepole-start type in-. duction motor 58; The motor 58, which includes a rotor 5 92fixedly connected to the; shaft 5'61and a stator 60; in: ductively .connectedto the rotor 59, is fixedly positioned inzthe casing 1 4 by connecting means. The connecting meanscomprise tie rods 64 which extend, through openings in the stator 6.0 andareconnected to thetop; wall of the casing 14" and to the mounting plate 28. Provided on each tie. rod 64 is a first shoulder 65 and a second shoulder 66. The upper end'of each tie rod 614; which is exteriorlythreaded, extends, through the top wall of the casing and the mounting plate, with the first shoulder 6-5being in engagement-with the top wall. A nut 67 is threaded on to the end of each tie rod to affix theupper endof'the tiered to the top of'casing 14' and the mounting plate 28; The lower'shoulder- 66 of the tie rod abuts the upper motor bearing-bracket 61 and the lower end of the tie rod is threaded to receive a nut 67 for securing the low-er motor bearing brackets 62' and thus securing the motor 58 in casing 14. Suitable lock Washers 68 may be provided between each nut 67 and the abutting surface of the lower motor bearing bracket and mounting plate 28, respectively.

Each motor bearing bracket 61- and 62is provided with:

a spherical retaining portion '70 and 71 respectively, adapted to opcratively support shaft bushings '72 and 73. Upper and lower spacer means74 and. '75 are. provided between the rotor 59' and the respective bushings '72 and 73. The motor lead lineslb are connected to a suitable source of power, as for example, a 12O volt alternating current supply, and the switchi f is provided to control the energization of" the Shaded pole induction motor 58: Provided in the opening 76 in mountingplate 28 is a grommet 78, which encircles the upper bushing or hearing '72 andprevents the entrance of chipped ice. or liquid fromv the ice-crushing chamber 32' into the motor compartmentdefined within casing 1 5;

Theupper end of shaft 56 carries a reduced threaded stud 82, thereby defining an annular, support shoulder 80 on the shaft 56. A cap nut 46 engages the threaded stud 82 andv supports the ice-crushing means 4% on the top of the shaft 56.

The motor 58, as aforenoted, is of the shaded-pole induction type, and is preferably of very inexpensive construction with anoutput preferably in the range of only 4 [016 watts and/or only 3 to 10 inch-ounces torque. Such limited'torque motors normally would be unsuccessful for utilization as a driving means for an ice. crusher means, such as at 4.0, for there is. a tendency for such low-output motors to stall.

By the present. invention there is provided an energy storage means separate from the rotor of the motor and connected to the rotor for maintaining rotation of, the motor during an ice-crushing operation. A very important feature of our invention is the coordinated'cooperation between the ice-crushing means 49, the limited torque induction motor 58, andthe energy storage means, or flywheel, which permits the use of, a relatively inexpensive shaded-pole induction. motor in an ice crusher and overcomes the tendency of such motor to stall; It will be understood thateither a two-pole or a four-pole induction motor can be employed in our ice crusher construction.

We have determined that by critically balancing the combinedweight of. the rotating components of the ice' I crusher assembly as above defined, rotation of the aforenoted limited torque motor may be maintained during an ordinary ice-crushing operation. We have found that the weight of'the energy storing means must be at least fifty percent of, the weight of the remainder of the rotating assembly, which comprises the motor rotor 59 (including the shaft 56).and the ice-crushing means 40, and preferably the ratio of Weight of energy storage means to weightofremainder of rotating. assembly is aboutZ: 1. Further, we.;have. found that the. combinedweight 0f the rotatingassembly. in anice crusher employinga small shaded-pole induction motor having an output in the range of only 4 to 16 watts and only 3 to 10 inch-ounces torque should preferably be in the range of 12 to 50 ounces. When-the rotating assembly weighs less than 12;, ounces; there is; insuflicient flywheel effect to crush an ice. cube. without'sttopping the motor or slowing it excessively. When the rotating. assembly weighs more than 50 ounces, the-motor. runs too slowly. and tends to overheat.

lnapractical application of this invention, it has been found that optimum ice-crushing action occurs when the energy "storage meansweigh abouttwice as much as the remainder of the aforesaid rotating assembly. Thus, when the total'weight of the ice-crushing means it) and rotor59-and shaft 56' is about 8 ounces, we have achieved excellent operational results with an energy storage means 85 weighing 14 ounces.

Turning now to FIG. 3, there is shown a cross sectional view taken substantially along the line 3-3 of FIG. 2. It is readily apparent that the passageway 36 is defined between the exterior wall of casing member 20 and by an interior wall 88 which is molded integral with the casing member 20.

The ice-crushing chamber 32 is defined, in part, by portions of the casing member 20, which include wall portions 33, 32a, 32b and 320. The walls 33 and 88 merge at an enlarged corner 35, which serves as a convenient anchor place for one of the assembly screws 30.

The ice-crushing-and-discharging means is provided with ice cutters 5t) and 52 having cutter edges 50a and 520, respectively, which face tangentially of disc 40, so that rotation of the disc 40 causes the cutter edges 50a and 52a to bite into the ice and to comminute it under the action of the rapid rotation of the disc 40. The edges of the ejector 54 face radially, so that the ejector 54 presents its broad face radially and operates to eifect discharge of the comminuted ice through the tangentially extending lateral discharge passageway 36. The cutters 50 and 52 are located at different spacings radially outwardly of the axis of rotation of the disc 40, the first cutter 50 being located innermost and the second cutter 52 being located radially about midway between the inner cutter 50 and,

the ejector 54, and the ejector 54 being located close to the outer periphery of the rotating disc 40. The upstanding cutters and ejector are structurally reinforced by the formation of embossed or dimpled reinforcement ribs 50b, 52b and 54b, respectively, adjacent the junctures of the respective members with the frusto-conical plate portion 48.

In FIG. 4 there is illustrated a plan view of the flywheel 84 of the present invention. The flywheel includes an annular hub portion 90 and a plurality of rigidifying rib elements 92 radiating outwardly from the hub portion 90. During rotation, rib elements 92 cause the flow of air over motor 58 to cool the same. The hub 90 is adapted to be connected to the lower end of shaft 56 by suitable fastening means, such asset screw 86. The weight of the rotating assembly is critical in producing the desired ice-crushing action. If there is not enough flywheel eifect, then the motor will stop or will be slowed excessively in ice-crushing operation. If the weight is too great, then the motor will run too slowly and as a result will overheat when it runs continuously. By maintaining the total weight of the rotating assembly between 12 and 50 ounces, there has been provided suflicient energy storage to maintain rotation during the requisite operational limits of a small shaded-pole induction motor having an output in the range of 4 to 16 Watts and 3 to inch-ounces torque.

By the present invention, there has been provided an economical construction for an ice crusher utilizing a lowcost shaded-pole induction motor having suitable potential energy in the rotating mass assembly so that when this energy is supplemented by the energy represented by the running power of the motor, there is sufficient kinetic energy to crush individual cubes of ice.

Insofar as common subject matter is concerned, this invention is an improvement over the invention disclosed in copending application Serial No. 5,054 filed by Alfred J. Huck on January 27, 1960, now US. Patent No. 3,051,401.

While there has been shown and described a particular embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the inventive concept and, therefore, it is intended in the appended claim to cover all such changes and modifications as fall within the true spirit and scope of the invention. Thus, while the energy storage means is shown as flywheel 84, it will be appreciated that energy storage means may be in different forms and different locations while still utilizing the princples of this invention.

We claim:

An ice crusher comprising, in combination, an upright passageway through which block ice may be introduced and advanced, an elongated passageway extending trans versely to said upright passageway and through which crushed ice is to be discharged, means defining an ice crushing chamber with which said upright and elongated passageways communicate, ice-crushing-and-discharging means including a rotary member in said ice-crushing chamber positioned to receive a block of ice from said upright passageway, for grinding up the block ice into relatively small flakes and chips within the ice-crushing chamber, and for directing the flakes and chips tangentially through said discharge passageway while preventing migration of the ground-up ice below said ice-crushing and discharging means, an elongated upright shaft having its upper end connected to said rotary member, a shadedpole induction motor providing a rotor on said upright shaft intermediate the ends of the shaft for rotating said shaft and said rotary member, said motor having an output in the range of only 4 to 16 watts and only 3 to 10 inch-ounces torque for driving said ice-crushing-and-discharging means, and a flywheel mounted on said upright shaft below the rotor, said flywheel being adapted to maintain the rotation of the motor during ice-crushing operation.

References Cited by the Examiner UNITED STATES PATENTS 2,904,268 9/59 Chappell et al 241- 3,051,401 8/62 Huck 241257 J. SPENCER OVERHOLSER, Primary Examiner. 

